I find the Prestige Creme de Cacao tastes just like whatever Young's use in their double chocolate stout.
Plenty of ways to get there.
I like the flavour of vanilla in brandy better than either whiskey or bourbon, some rums work well to, largely a matter of personal taste and a fun place to play.
I did it according to this scheme. I took roasted barley, chocolate and caramel malt, and put it in a small linen bag. Then he put the bag in a container with 1.3 gallons of hot water (temperature up to 167
Fahrenheit) and heated the water to a boil over medium heat. After that, I took out the bag and diluted the resulting wort with water to 5 gallons. He boiled for 60 minutes, five minutes before turning off the heating, he added defatted cocoa powder to the boiling wort. Recipe for 4 gallons of beer approx. Primary fermentation - 9 days at 65-68 F, secondary - 15 days